Scanning line bar in Project - Someone explain! Please.

Hi Tigervision,

Welcome to Apple Support Communities.

It sounds like you are describing two different iMovie features, the Playhead and the Skimmer. Take a look at the iMovie Help article linked below for details about usage of each feature.

iMovie Help: Skimming and the playing overview

http://help.apple.com/imovie/mac/10.0/#mov819403e17

You use two tools to preview and play back media in the viewer:

• The playhead marks the current position in a clip or movie. You can move the playhead by clicking another area of the clip or movie. You drag the playhead to scrub, or play back your clip or movie from the current playhead position.The playhead appears as a white vertical line that is fixed in place unless you move it or click elsewhere.
• The skimmer lets you preview movies and clips without affecting the playhead position. You use the skimmer to skim, or freely move over movies and clips to play them back at the position and speed of the pointer.The skimmer appears as an orange vertical line as you move the pointer over the area you’re skimming. Snapping makes the skimmer snap to edit points and the edges of clips. If you have snapping turned on, the skimmer turns yellow when it snaps to a position.

If both the playhead and skimmer are present in the same clip, the skimmer becomes the default position for playback or editing.

If the skimmer is not present in a clip, the playhead assumes the default position.

I hope this helps.

-Jason